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Hi guys, I've got a really strange problem with the RS4. It has the light sensitive dashboard lights, so regardless of whether the headlights are on or not, the dials light up according to the daylight around the car - in other words as you go through a tunnel or under trees the speedo illumination increases, etc, so you can still see what speed you are doing. I'm sure this is a std feature of all RS4's, so you are all probably aware of it anyway.

Anyway, recently had the bluetooth kit fitted and since then all the dashboard/dial lights go really dim when I go through a tunnel and become really bright when I'm in direct sunlight Almost like something has been reversed.

What I wondered is whereabouts is the light sensor that controls this function and could it have become unplugged and then plugged back in the wrong way round or something?

I know it sounds like a silly problem, but it is really stressing me out, so any help mucho appreciated.

Ta

Pretty sure the sensor is in the mount of the rear view mirror.

When the bluetooth is installed then a mic should also be installed into the roof light/switch panel on the top of the windsceen near the mirror - could something have been disturbed in this area like a light sensor? Just a thought.

Graham

Love_iTT wrote:When the bluetooth is installed then a mic should also be installed into the roof light/switch panel on the top of the windsceen near the mirror - could something have been disturbed in this area like a light sensor? Just a thought.

Graham

Hmmm, that's kind of what I was thinking. Does anyone know if the sensor is definitely in the roof light aperture bit? and if so, what does it look like.

Ta again

I had this on a car a few years back. I had a Nokia phone kit fitted with an adaptor between the radio and the phone kit to control mute, sound output etc. This had been made wrong at the factory and tuned off the dash lights when it was dark and on when it was light! A quick mod from the phone engineer (2 wires swaped) and all was sorted!

can't recall but there is a pix in my BT install thread

My car has the phone kit as standard and does this behaviour too. I thought it was designed to remind you to put on the headlights - it seems to operate at the same level of light as the auto setting for the headlights.

daviesd wrote:My car has the phone kit as standard and does this behaviour too. I thought it was designed to remind you to put on the headlights - it seems to operate at the same level of light as the auto setting for the headlights.

When you say it behaves like it too, do you mean that the dash lighting gets darker as the surrounding daylight gets darker, or do you mean that the dash lights get darker when it is brighter outside?

Cheers

daviesd wrote:My car has the phone kit as standard and does this behaviour too. I thought it was designed to remind you to put on the headlights - it seems to operate at the same level of light as the auto setting for the headlights.

This is my understanding as well (and I've read it somewhere - probably the handbook)

The needles and dials illuminate in daylight, but dim as it gets dark to remind you that your lights aren't on. I've never really seen this in action as I've got auto-lights on all the time - this way the lights come on instead of the dials dimming

Wow, I hope you are right.... and all along it's just me being a plonker!

I'm sure they used to get brighter as the external environment got darker. Perhaps its just me.

Dom81 wrote:

daviesd wrote:My car has the phone kit as standard and does this behaviour too. I thought it was designed to remind you to put on the headlights - it seems to operate at the same level of light as the auto setting for the headlights.

This is my understanding as well (and I've read it somewhere - probably the handbook)

The needles and dials illuminate in daylight, but dim as it gets dark to remind you that your lights aren't on. I've never really seen this in action as I've got auto-lights on all the time - this way the lights come on instead of the dials dimming

They usually dim when the headlights are on (based on the assumption that one would turn on the headlights when the environment is dark, in the case of the Audi with the ambient light sensor, it may get smart about it and dim it in darker environments with or without the headlamps turned on) to minimize contrast, otherwise the dials would be glaring and distracting, not to mention that it will tire your eyes out sooner from the added strain, thereby making it less pleasant to drive.

This is a common feature in most cars today, AFAIK, but not usually documented

ghoonk wrote:

Dom81 wrote:

daviesd wrote:My car has the phone kit as standard and does this behaviour too. I thought it was designed to remind you to put on the headlights - it seems to operate at the same level of light as the auto setting for the headlights.

This is my understanding as well (and I've read it somewhere - probably the handbook)

The needles and dials illuminate in daylight, but dim as it gets dark to remind you that your lights aren't on. I've never really seen this in action as I've got auto-lights on all the time - this way the lights come on instead of the dials dimming

They usually dim when the headlights are on (based on the assumption that one would turn on the headlights when the environment is dark, in the case of the Audi with the ambient light sensor, it may get smart about it and dim it in darker environments with or without the headlamps turned on) to minimize contrast, otherwise the dials would be glaring and distracting, not to mention that it will tire your eyes out sooner from the added strain, thereby making it less pleasant to drive.

This is a common feature in most cars today, AFAIK, but not usually documented

I think ghoonk is right - I've noticed my B5 RS4 does this; dims when surrounding light gets darker and brightens when it gets brighter.
As already mentioned, I think it's more a convenience feature in that it's to reduce eye strain and interior lighting, to make a more subtle view in the interior at night.